This invention relates to a method and novel apparatus for forming ice objects of intricate configuration, and has particular application in the formation of decorative ice statuary and the like to be utilized at banquets, wedding receptions and similar festive occasions to decorate the tables in a unique and impressive manner. Such ice statuary also has application in the decoration of windows of restaurants and the like.
Ice sculptures have long been appreciated for their aesthetic appearance, due primarily to the smoothly flowing and/or artistic surfaces of the ice and to the clarity of the ice and its ability to transmit light therethrough. Ice sculptures have often been used as distinctive decorations for banquets, celebrations, and many other such business or joyous occasions. When fashioned as bowls, the ice sculptures can also provide a desired cooling effect upon the punch or other liquid contained in the bowl.
In the past, ice sculptures involving unusual shapes have generally been fabricated from large blocks of clear ice, using special tools to chip, form, and smooth the ice. Chain saws are frequently used to form large ice sculptures. Such techniques involve a great deal of the mass of the original block of ice being wasted. Moreover, the labor involved in forming the ice sculpture has resulted in high cost of the sculptures. In many localities, artists of sufficient skill to carve attractive ice statuary are simply not available.
Some ice statuary has earlier been created by the use of molds formed from metal or the like, with punch bowls and other cavity-containing objects being typical. Such metal molds are filled with water and then immersed to an appropriate extent in a cooling medium such as a tank of brine or glycol equipped with refrigeration coils. Such immersion is usually within an inch or two from the top of the mold. To assure clarity of the ice, compressed air is inserted near the bottom of each mold during the freezing process. After ice has formed to a desired thickness, the mold is removed from the tank and then maintained in an inverted position until a degree of melting takes place and the ice object drops out of the mold.
One distinct advantage of the use of molds of this type is that these improved techniques have permitted the inclusion of various decorative elements, such as flowers, bright objects, letters, paper letters, or other decorative or visual indicia, within the structure of the ice bowl.
It is quite difficult by the use of metal molds, however, to create ice objects of intricate shape, and any "undercut" created in the mold would make removal of the ice object from the mold nearly impossible.
Exemplary of the prior art teachings is U.S. Pat. No. 2,545,592 to Sherbloom wherein is disclosed a method of forming ice molded figures by the utilization of a split mold adapted to be immersed in a can that is subsequently placed in a refrigerated tank of brine. However, the apparatus necessary for the practice of prior art methods has been relatively cumbersome and has precluded the adoption of these methods by relatively small restaurants, hotels and the like.
A method of molding ice sculptures is described in U.S. Pat. No. 4,206,899 to Whitehead, with this method involving supporting a water-filled flexible mold in an inverted position within a rectangular outer box. Because of the hydrostatic pressure of the water, especially with large sculptures, the flexible mold must be of sufficiently thick wall structure to prevent distortion. In addition, this method uses a walk-in freezer or the like, which causes a freezing of the mold from all sides including the top of the water level. This in turn causes the ice to "crust over" which traps in all the air on the inside of the mold, causing cloudy and cracked ice.
The necessary thick-walled flexible molds are expensive to make and difficult to peel off the ice sculpture. It is also found that sculptures made by the method and apparatus of U.S. Pat. No. 4,206,899 contain cracks which detract from the appearance and structural integrity of the sculpture. Such sculptures are typically quite cloudy due to lack of circulation, and in addition, the mold must be placed in a freezer.
Whitehead utilizes a mold in its base through which support wires are inserted. The mold is inverted, base up, within a box slightly larger than the mold with the wires engaging the open top of the box and supporting the mold. After the mold is filled with water and frozen, it is removed from the box and the mold is stripped from the frozen sculpture.
The single part mold used by Whitehead is of such a nature as to be restricted to sculptures which taper more or less uniformly from top to bottom so that the mold can be removed from the finished sculpture. The Whitehead mold could not, for example, be used to mold an ice sculpture having relatively small top and bottom portions and an enlarged central portion. Furthermore, the Whitehead mold can only be used to make relatively small ice sculptures due to the nature of the flexible material Whitehead uses for his molds. If his molds were larger, the weight of the water would expand the bottom of the mold.
Although it has previously been known to create crystal clear ice by the use of reusable metal molds, in order to prevent cloudiness of the resulting ice, it has been common practice to circulate the water in the mold to remove air bubbles. Such circulation is typically brought about by an aeration arrangement. Without sufficient circulation, crystal clear ice simply cannot be obtained.
The Reynolds U.S. Pat. No. 1,476,220 entitled "Method of and Means for Agitating Water in Ice Making Apparatus" teaches the use of an ice or brine tank 10 within which are placed ice cans 11 containing the fresh water to be frozen into ordinary ice blocks. This patentee utilizes what he calls an agitator pipe 18 in each ice can 11, for the introduction of air supplied from a blower 12. Reynolds explains that as a result of agitating the water, the impurities will collect. When the water has changed to ice, except for a small core in the middle of the can, this water with the impurities may be removed, and distilled water substituted.
It is obvious that Reynolds discloses nothing pertaining to the creation of ice objects of intricate configuration by the use of flexible molds, for he is entirely concerned with the creation of ordinary ice blocks, presumably for home or commercial use.
It is obvious that when using reusable metal molds, one end of the mold must be larger than the other end, and no "undercuts" may be utilized. Otherwise, it would not be possible to remove the completed ice structure without destroying the mold or else melting substantial portions of the ice object.
An alternative to the use of metal molds has been the use of hard plastic molds, with in many instances such molds being destroyed when the ice sculpture is to be removed. However, this is obviously an expensive approach.
In the Sherbloom U.S. Pat. No. 2,545,592 it was taught that two-part molds can be utilized, which molds are secured together and then immersed in brine or other cold liquid in order to bring about the freezing of the contents of the mold. However, nothing is said in Sherbloom about providing aeration, so the ice objects resulting from the use of Sherbloom's technique will be of cloudy ice rather than crystal clear ice. Even if Sherbloom created the parts of the mold that come together, this would not allow sufficient circulation, causing dead spots in the mold where the water is stagnant, thus creating cloudy pockets of ice.
Another Sherbloom patent is U.S. Pat. No. 2,939,299, which also utilizes two-part molds of hard material. Sherbloom obviously discovered that he could not create objects of crystal clear ice without aeration, so in Column 4 of this more recent patent, Sherbloom describes how his mold sections are aerated continuously through air hoses 48 during the freezing process to produce a frozen object characterized by the clarity of the ice from which it is molded. How Sherbloom prevents his air line from freezing in place is not described, however.
It is to be noted from the drawings of the Sherbloom U.S. Pat. No. 2,939,299 that the objects he creates are comparatively flat. In other words, two dimensional objects can be created, but not three dimensional objects. Three dimensional objects have deep crevices. Sherbloom utilizes hard, non-flexible molds, which simply cannot have three dimensional, lifelike undercuts.
With reference to the Whitehead U.S. Pat. No. 4,206,899, it will be noted that this patentee utilizes molds fabricated from form-retaining, flexible, resilient plastic material. However, from the material he utilizes for his molds, it is apparent that if the molds are too thick, it will be exceedingly difficult to remove the completed ice sculpture from the mold, but on the other hand, if the material from which the mold is made does not have enough character or thickness, the object created in the mold will take on a "bulged out" appearance and not be faithful to the intended configuration.
It is significant to also note with respect to the Whitehead patent that he may utilize the environment of a walk-in freezer for bringing about the freezing of the water in the mold, but in such instance, the icing over of the water in the top of the mold will prevent any effective aeration of the water in the mold. As a result, cloudy ice will predictably result from the utilization of this Whitehead technique.
With reference to the DeGaynor U.S. Pat. No. 4,550,575 entitled "Ice Bowl Freezing Apparatus," it is obvious that no intricate shapes are possible, for when using metal molds, the ice object would be impossible to remove should any "undercut" be present. DeGaynor recognizes the advantage of providing air circulation, but it would be impossible utilizing DeGaynor's technique to create any ice object of intricate configuration, such as statuary or the like.
With reference to the Wu U.S. Pat. No. 4,562,991, it will be noted that although Wu employs a reusable ice mold that allegedly produces intricate ice objects, it is obvious from FIGS. 1 and 6 that the fowl depicted in these figures is of "chunky" and non-intricate configuration. Also, because no aeration or circulation is mentioned, Wu will not be able to create crystal clear objects by the practice of his method.
The Noel U.S. Pat. No. 4,669,271 is concerned with multi-part molds, but he utilizes his molds in a walk-in freezer. For this reason, the upper surface of the water in the mold will ice over, thus trapping inside the mold, any air bubbles that may be present, thus resulting in the formation of a cloudy ice object. Most importantly, no circulation is possible.
The Parmacek et al U.S. Pat. No. 4,739,963 is concerned with plastic molds, with his improvement being a hollow core formed in the base of the mold to allow for expansion in the mold when it changes phase into ice. Because of this arrangement, these patentees maintain that they reduce stress and cracking in the finished ice form. The Parmacek et al patent process allows one-time only use of the mold, with the mold being destroyed after use.
However, nothing is said in the Parmacek et al patent about the use of aeration or circulation, so crystal clear ice will not result from a practice of that method.
The Tu U.S. Pat. No. 4,807,844 utilizes a mold of elastomeric material, but he places his mold in a walk-in freezer and says nothing about aeration. Inasmuch as the placement of the mold in a walk-in freezer necessarily brings about an icing over of the water in the top of the mold, any circulation induced by the utilization of compressed air or any other method would result in the entrapment of the bubbles in the ice. Tu's method will definitely not result in the creation of crystal clear ice.